/*
 * Copyright 2010, Andrew M Gibson
 *
 * www.andygibson.net
 *
 * This file is part of DataValve.
 *
 * DataValve is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * DataValve is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with DataValve.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.fluttercode.datavalve.provider.jdbc;

import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.Map;

/**
 * This class is used to return the results in the mapped sql dataset without
 * having to create a class to return the results in.
 * The results are returned in this class as a map of values. To access a field
 * value, just call {@link TableRow#getValue(String)} and pass in the name of
 * the field to access. The lookup is case sensitive.
 *
 * @author Andy Gibson
 */
public class TableRow {

    /** The <code>values</code> map holds the values */
    private Map<String, Object> values = new HashMap<String, Object>();

    /**
     * Helper method to add a new value into the row
     *
     * @param column Name of the column to add
     * @param value Value of the column to add
     */
    public void add(String column, Object value) {
        values.put(column, value);
    }

    /**
     * Returns the value of the passed in column name for the row in the
     * {@link ResultSet} this object represents.
     *
     * @param columnName name of the field to return
     * @return the value of that column for this row.
     */
    public Object getValue(String columnName) {
        if (values.containsKey(columnName)) {
            return values.get(columnName);
        }
        throw new IllegalArgumentException(String.format(
                "Dataset does not contain field '%s'", columnName));
    }

    /**
     * A static factory method that creates and initializes a TableRow instance
     * for the current row of the passed in {@link ResultSet}.
     *
     * @param resultSet The {@link ResultSet} containing the values we need to load into the TableRow instance.
     * @return a new TableRow instance initialized with the values from the {@link ResultSet}.
     * @throws java.sql.SQLException
     */
    public static TableRow createTableRowFromResultSet(ResultSet resultSet) throws SQLException {
        TableRow result = new TableRow();
        ResultSetMetaData metadata = resultSet.getMetaData();
        for (int i = 0; i < metadata.getColumnCount(); i++) {
            int colIndex = i + 1;
            String name = metadata.getColumnName(colIndex);
            Object value = resultSet.getObject(colIndex);
            result.add(name, value);
        }
        return result;
    }
}
